Squalor
I believe the answer is:
filth
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">squalor</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for filth that I've seen before include "Squalor" , "Real dirt or obscenity" , "Carrion" , "Disgusting dirt or obscenity" , "Muck" .)